This disclosure relates generally to online systems, and more specifically to selecting content for presentation to users of an online system.
An online system allows its users to connect to and to communicate with other users of the online system. Users create profiles on an online system that are tied to their identities and include information about the users, such as interests and demographic information. The users may be individuals or entities such as corporations or charities. Users may share information about themselves via an online system by posting content for presentation to other online system users.
To further encourage interaction with the online system by users, the online system may generate content describing actions performed by online system users for presentation to other online system users, such as online system users connected via the online system to an online system user who performed an action. Online system users may interact with content provided by the online system. For example, an online system user may indicate a preference for content provided by the online system, share the content with additional users provided by the online system, or comment on the content provided by the online system. The online system may account for interactions with content by a user when selecting additional content for presentation to the user.
Conventionally, online systems select content for presentation to a user based on measures of relevance between the user and various content. A measure of relevance between the user and content may be based on prior user interactions with content, connections between the user and other users associated with the content, or characteristics of the user. Presenting content with high measures of relevance to the user increases user interaction with the online system, providing opportunities for the online system to generate revenue (e.g., by presenting content to users for which the online system receives compensation for presenting). However, certain users of an online system have limited connections to additional users of the online system, which may limit selection of content by the online system for presentation to the certain users. For example, if a user who recently created a user profile on the online system and has not established connections to many additional users, the online system has limited information associated with the user for selecting content to present to the user, which is likely to limit interaction with the online system by the user.
To increase opportunities for users for whom the online system has limited information, the online system may use common attributes, such as interests and demographic information, between the user and additional users. For example, the online system presents content to a user that is associated with additional users to whom the user does not have a direct connection (e.g., additional users who are connected to users to whom the viewing user is connected). As an additional example, the online system presents content to a user that is associated with additional users who attended the same university as the user. However, using common attributes between a user and additional users to select content may cause the online system to present content to the user that is associated with additional user with whom the user lacks a real-life relationship. Moreover, if a user does not have connections to additional users of the online system or has not provided information to the online system describing the user's characteristics, the online system may still lack information to select content for presentation to the user, limiting interaction between the user and the online system.